Oh silly me. I got it backwards.
At the washing machine, if available, I have used a $5 "Y" faucet adapter from HD/Lowes with a brass reducing adapter, also from HD/Lowes to connect one output end to the RO line. The RO unit hangs on the wall behind the washing machine and a 5 gal bucket fills as it's sitting on top of the machine. If it overfills, the spill simply drains into the washing machine.
Aloha.
Mark
Edited by Mark Peterson - February 17 2016 at 7:19am